Metabolism and Photosynthesis Quiz

What is metabolism?

• The breakdown of glucose

• The sum of all chemical reactions in a cell

• The creation of ATP

• The flow of electrons

Answer explanation

Metabolism refers to the sum of all chemical reactions in a cell, including both the breakdown of substances and the synthesis of new compounds. This encompasses processes like energy production and nutrient utilization.

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-5

Which type of reaction breaks down large molecules into smaller ones?

• Anabolism

• Catabolism

• Reduction

• Photosynthesis

Answer explanation

Catabolism is the metabolic process that breaks down large molecules into smaller ones, releasing energy. In contrast, anabolism builds larger molecules from smaller ones. Therefore, the correct answer is catabolism.

Tags

NGSS.HS-LS1-6

Which molecule is an example of potential energy?

• ATP

• A moving car

• Water flowing over a dam

• A person walking

Answer explanation

ATP is a molecule that stores potential energy in its high-energy phosphate bonds, making it an example of potential energy. In contrast, a moving car, flowing water, and a walking person represent kinetic energy.

Which law of thermodynamics explains that no energy transfer is 100% efficient and some energy is lost as heat?

• First Law

• Second Law

• Third Law

• Law of Conservation of Energy

Answer explanation

The Second Law of Thermodynamics states that energy transfers are never 100% efficient, as some energy is always lost as heat. This principle highlights the inherent limitations in energy conversion processes.

What is the molecule used as the energy currency in cells?

• NADH

• ATP

• Glucose

• FADH2

Answer explanation

ATP (adenosine triphosphate) is the primary energy currency in cells, providing energy for various cellular processes. While NADH and FADH2 are involved in energy transfer, ATP is the direct source of energy for cellular activities.

Tags

NGSS.HS-LS1-7

What is the process of adding a phosphate group to ADP to form ATP called?

• Hydrolysis

• Phosphorylation

• Oxidation

• Fermentation

Answer explanation

The process of adding a phosphate group to ADP to form ATP is called phosphorylation. This reaction is essential for energy storage in cells, while hydrolysis refers to breaking down ATP, and oxidation and fermentation are different metabolic processes.

What type of reaction releases energy?

• Exergonic

• Endergonic

• Anabolic

• Redox

Answer explanation

Exergonic reactions release energy as they proceed, making them spontaneous. In contrast, endergonic reactions require energy input, while anabolic reactions build molecules and redox reactions involve electron transfer.

Tags

NGSS.HS-PS1-4

What enzyme lowers the activation energy of reactions in cells?

• ATP synthase

• Hexokinase

• Catalase

• All enzymes

Answer explanation

All enzymes lower the activation energy of reactions in cells, facilitating biochemical processes. While specific enzymes like catalase and hexokinase have unique functions, the statement applies to all enzymes collectively.

Which factors affect enzymatic activity?

• pH, temperature, and substrate concentration

• Substrate size and temperature

• Enzyme shape and size

• None of the above

Answer explanation

Enzymatic activity is influenced by pH, temperature, and substrate concentration. These factors affect the enzyme's ability to bind to substrates and catalyze reactions, making this choice the most comprehensive.

In competitive inhibition, the inhibitor binds to:

• The active site

• An allosteric site

• The substrate

• Another enzyme

Answer explanation

In competitive inhibition, the inhibitor competes with the substrate for the active site of the enzyme. By binding to the active site, it prevents the substrate from attaching, thus inhibiting the enzyme's activity.